Cutting machine



March 6, 1962 3,023,746

W. M. COOPER CUTTING MACHINE Filed Aug. 5, 1960 2 Sheets-Sheet 1 INVENTOR WILLIAM M, COOPER BYco'z/wwwat pmvell ATTORNEYS March 6, 1962 w. M. COOPER CUTTING MACHINE 2 Sheets-Sheet 2 Filed Aug. 5, 1960 INVENTOR WILLIAM M. COOPER BY (l -R ATTORNEYS United States Patent 3,023,746 CUTTING MACHINE William M. Cooper, St. Louis, Mo., assignor to Champion Manufacturing Company, St. Louis, Mo., a corporation of Missouri Filed Aug. 5, 1960, Ser. No. 47,726 12 Claims. (Cl. 12513) This invention relates generally to improvements in a cutting machine, and more particularly to an improved operating mechanism in a masonry saw for precisely adjusting the heighth of the cutting assembly above a work table.

It is an important objective of the present invention to provide a masonry saw in which a cutting assembly is swingably mounted on a vertically reciprocal support, and means for readily raising or lowering such support selectively to adjust the heighth of the cutting assembly.

An important object is achieved by the provision of a manually operated element that can constitute advantageously either a handle or a foot pedal, pivoted to the machine frame, and a suitable linkage means operatively interconnecting the manual element to the cutting assembly support for selectively reciprocating the support upon pivotal actuation of such manual element.

Another important object is realized by operatively connecting a tension spring to one of the links of the linkage means described previously so that the spring tends to maintain the support and hence the cutting assembly substantially midway between its limits of reciprocating movement.

Other important advantages are provided by the particular structural arrangement and connection of the spring in that the force exerted on the manual element by the operator to lift the support and cutting assembly is substantially the same as the force exerted to lower the assembly from its balanced position.

Still another important object is afforded by the structure of the linkage that provides the above mentioned functional advantages, such linkage including a lever pivoted to the frame, a link attached to the lever and rotatable therewith, a bar pivotally interconnecting the link with the support, and a rod pivotally interconnecting the manual element to the lever so that upon actuation of the manual element, the lever will be rotated by the rod, and the lever in turn will act through the link and bar to raise or lower the cutting assembly support.

Yet another important object is achieved by connecting one end of the tension spring to the frame and the other end to the pivoted lever so that the tensional force exerted on the lever tends to rotate the lever and its attached link in a direction so that the bar lifts and holds the support and cutting assembly substantially halfway in its range of reciprocal movement.

Another important object is to provide a heighth adjusting mechanism in a cutting machine of this type that is simple and durable in construction, economical to manufacture, efiicient in operation, and which can be readily operated by any one with little or no instruction.

The present application is a continuation-in-part of co-pending application Serial No. 192, filed January 4, 1960, by William M. Cooper, for cutting machine.

The foregoing and numerous other objects and advantages of the invention will more clearly appear from the following detailed description of a preferred embodiment, particularly when considered in connection with the accompanying drawings, in which:

FIG. 1 is a side elevatoinal view of the cutting machine showing the support and cutting assembly in a lowered position;

FIG. 2 is a rear elevational view as seen from the right of FIG. 1, and

3,@Z3,745 Patented Mar. 6, 1962 FIG. 3 is a side elevational view of the cutting machine showing the support and cutting assembly in a raised position.

Referring now by characters of reference to the drawing, it is seen that the cutting machine includes a frame generally designated at 10, the frame 19 having a pair of front legs 11 and a pair of rear legs 12. A rectangular, open top pan 13 interconnects the upper portion of frame legs 11 and 12. A pair of base channels 14 extend between and support the lower ends of a front leg 11 and a rear leg 12 at each side of the cutting machine.

An intermediate platform 15, disposed substantially midway between the pan 13 and the base channels 14, is secured to and extends between the front and rear legs 11 and 12.

A work table 16 is mounted on and is supported by the frame 10. More specifically, the work table 16 includes rollers 17 that seat on and engage side rails 18 formed by the uppermost margins of pan 13 for horizontal reciprocating movement in a fore and aft direction on the machine.

Mounted for vertical reciprocating movement on the frame 10 is a support generally indicated at 20. This support 29 includes a pair of laterally spaced, cylindrical sleeves 21 disposed at the rear of frame 10 and formed as a vertical continuation of the rear legs 12. The sleeves 21 extend upwardly above the open top pan 13 and above the work table 16. A vertical cylindrical post 22 is slidably mounted in each of the cylindrical sleeves 21, the posts 22 being selectively movable to the retracted position illustrated in FIGS. 1 and 2 and selectively movable to the extended position illustrated in FIG. 3. The posts 22 are rigidly secured by a transverse beam 23.

Flexible boots 24 provide dust seals for the connection between the sleeves 21 and the posts 22. Each boot 24 has one end secured to one of the posts 22 and the other end secured about the sleeve 21 with which the post is associated. The boots 24 are flexible to permit ready reciprocatoin of the posts 22 without any binding action.

Secured to the top of each post 22 is a bearing block 25 in which is formed an inclined forwardly facing notch 26. An axle 27 extends between the bearing blocks 25 and is located for horizontal pivotal movement in the notch 26.

The cutting assembly referred to at 30 is swingably mounted on support 20 so as to move a cutting tool 31 toward and away from the work table 16. More partic ularly, the cutting assembly 3i) includes a platform 32 fixed to axle 27 and disposed between the bearing blocks 25. The platform 32 is normally located in a horizontal initial position relative to its pivotal axis provided by axial 27. A motor 33 is mounted on platform 32 and is operatively connected to the cutting tool 31 by a belt drive 34. The cutting tool 31 is in the nature of a masonry saw rotatively mounted to one end of platform 32 at one side of the pivot axis 27.

A recirculating system (not shown) of a conventional well known type may be provided to direct a coolant to the tool 31. which coolant is collected by the pan 13.

Pivotally connected to the frame 1 about a horizontal axis is a pedal 40. Specifically, the pedal 40 is attached by pivot pin 41 between a pair of laterally spaced vertical bars 42 extending between and attached to a cross brace 43 and the bottom of pan 13. The pedal 40 extends forwardly from its pivotal axis provided by pivot pin 41 to a position adjacent and between the front frame legs 11. The forward end of the pedal 40 is provided with a foot plate 44.

In its normal initial position, the pedal 40 is disposed substantially horizontal relative to its pivotal axis. As is best seen in FIG. 1, a stop member 45 is threadedly attached to the intermediate frame platform 15, the stop pedal 48 relative to its pivotal axis can be varied s'elec tively upon threaded adjustment of the stop member 45.

A tension spring 47 operatively interconnects the frame platform and the pedal 40, and tends to urge the pedal 40 upwardly against the stop member 45, and hence tends to hold and maintain the pedal 40 in its normal initial position illustrated in FIG. 1.

Operatively interconnecting the cutting assembly 30 and the pedal 48 is a heighth adjustment means that serves to swing the cutting assembly 30 about axle 27 upon pivotal movement of pedal 40 about its pivotal axis. This heighth adjustment means includes a heighth adjustment bar 50 having one end pivotally attached to the platform 32 by a horizontal pivot pin 51, such pivotal connection being to the platform 32 on the opposite side of axle 27 from the cutting tool 31. The opposite end 52 of adjustment bar 58 extends downwardly,

A lift link 53, afforded by a pair of compatible link members, has one end pivotally connected by a horizontal pivot pin 54 to the pedal 40 at a point spaced forwardly from the pedals pivot pin 41. The other end of the lift link 53 extends upwardly.

Extending between the adjustment bar 50 and the lift link 53 is a rocker arm 55 consisting of a pair of link members. One end of the rocker arm 55 is pivotally attached to the upper end of the lift link 53 by a horizontal pivot pin 56. The other end of the rocker arm 55 is pivotally attached to the lower end 52 of the heighth adjustment bar 50 by a horizontal pivot pin 57.

A stabilizer means operatively interconnects the support 2 0 to the frame '10 and to' the previously described heighth adjustment means so as to permit the heighth adjustment means to maintain the cutting assembly 30 in its initial horizontal position upon reciprocation of support 20, and yet enable swinging movement of the cutting assembly 30 about its axle 27 upon actuation of pedal 48.

The stabilizer means includes a pair of spaced brackets fixed to the cross beam 23 of the support 20, and hence constitutesa part of such support. One end of a link stabilizer 61, consisting of a pair of link members, is attached pivotally to the support brackets 60 by a horizontal pivot pin 62. The link stabilizer 61 extends down wardly. \A floating link 63, consisting of a pair of link members, has one end pivotally attached to a horizontal pivot pin 64 to the rigid vertical frame bar 42. The other end of the floating link 63 is pivotally connected to the lower end of the link stabilizer 61 by a horizontal pivot pin 65.

A pivot means provided by the horizontal pivot pin 66 operatively interconnects the floating link 63 with the rocker arm 55. The floating pivot pin 66 is located between the pivot pins 56 and 57 at the end of the rocker arm55 and is located between the pivot pins 64 and 65 at the end of the floating link 63. It will be particularly noted that the floating pivot pin 66 movesin an are about pivot pin 64 as the floating link 63is pivotally moved upon reciprocation of the support 20.

It will be immediately realized that while the rocker arm55, lift link 53, link stabilizer 61 and floating link 63 each consist of a pair of links for rigidity and strength in the embodiment disclosed, a single member may be used and interconnected to operate in the same manner and provide the same function.

The operating mechanism for reciprocating the support includes a bell crank constituting a manual element 70 pivoted to the frame 10 at one side of pivot pin 71. One arm 72 of the manual element 76 extends forwardly of the frame and constitutes a handle capable of being gripped by the operator. The other arm 73 of ma ua ment. xt nd arwar m t e. pivot pin 71. A plate 74 is attached to the front arm 72 so as to be rotatable with the manual element 70. Formed inplate 74 is an arcuate slot 7'5 that is adapted to receive a locking member 76 attached to and carried by the front frame leg 11.

Extending transversely of the frame 10 rearwardly of the manual element 70 is a shaft 77. More particularly,

the shaft 77 is rotatively mounted on brackets 80 attached to the opposite rear legs 12.

A lever 81 has one end attached to theshaft 77 at the same side of the frame 10 at which the manual element 78 is located. A rod 82 operatively interconnects the manual element 70 and the lever 81. Specifically, one end of rod 82' is pivotally attached to the other end of lever 81. while the other end of rod 82 is pivotally attached to the rear arm 73 of manual element 70.

A link 83, afforded by a pair of spaced parallel link members, is attached to the shaft 77 so as to be rotatable therewith. The link 83 is spaced from the lever 81 and is located toward the center of frame 10. A bar 84 operatively interconnects the support 20 with the link 83. The bar 84 consists of a pair of spaced parallel link members, one end of bar 84 being pivotally attached to the rearmost end of link 83 while the other end of bar 84 is pivotally attached to brackets 85 that are fixed to the transverse beam 23.

While the link 83 and bar 84 each consist of a pair of link members for rigidity and strength in the embodimentdisclosed, a single member may be used and interconnected to operate in the same manner and provide the same function.

A tension spring 86 operatively interconnects the link age means described above to the frame 10'so as to main tain the support 20 substantially midway in its range of reciprocal movement. Particularly, one end of spring 86 is attached to the lever 81 while the opposite end of spring 86 is attached to the frame 10substantially in the region of the pivot pin 71.

As viewed in FIG. 1, the tensional force of spring 86 tends to rotate the shaft 77 in a counterclockwise direction. When the manual element 70 is released so that the linkage means can assume its normal static position, the spring 86 acts through link 83 and bar 84 to hold the support 20 midway between its lowermost position shown in FIG. 1 and its uppermost position shown in FIG. 3.

To lower the support 20, the manual element 70 is actuated by the operator to pivot such element in a clockwise direction as viewed in FIG. 1. Upon pivotal actuation of manual element 70, the rod 82 acts to rotate the shaft 77 in a clockwise direction. Suchoperation causes the link 83 and bar 84 to lower the support 20. It will be noted that upon lowering the handle arm 72 of the manual element 7 0, suflicient force must be exerted by the operator to extend the tension spring 86 and thereby increase the tensional loading of such spring 86. If the manual element is not locked in this adjusted position but rather released, this increased tensional loading of spring 86 Will automatically raise the support toits balanced midway height position. However, the support 20 can be maintained in any adjusted lower position by tightening the locking member 76 to clamp the plate 74 against the frame 10.

In order to raise the support 20, the handle arm 72 of the manual element is lifted so as to pivot the manual element 7% clockwise about the pivot pin 71. Consequently, the rod 82 acts to rotate shaft 77 in a counterclockwise direction, and thereby causes link 83 to raise bar 84 and the support 28. In raising the support 20 upwardly above its balanced midway height position, the operator must exert sufficient force on the manual element 70 to overcome the weight of the support and cutting assembly. Of course, the operator is assisted in this operation by the tensional force of spring 86. Again, the support 20 can be held in any adjusted heighth position merely by tightening the locking member 76 to clamp the plate 74 against,

the frame 10, thereby holding the manual element 70 in adjusted pivoted position.

Because of the particular structural arrangement and connection of the spring 86 relative to the linkage means, the force exerted on the manual element 70 to lift or lower the support and cutting assembly from its balanced midway height position is substantially the same.

To describe the operation of the cutting machine it will be assumed that the support 20 is located in its lowermost position as is illustrated in FIGS. 1 and 2. In order to lower the support 20, the handle arm 72 is lowered and the manual element 70 pivoted counterclockwise. The linkage means provided by rod 82, lever 81, link 83 and bar 84 acts to lower the support 20 against the loading of spring 86. When the support 20 is located in the desired height position, the locking member 76 is tightened to fix the manual element 70. The cutting tool 31 is now in its lowermost height position above the work table as determined by the support 20.

The pedal 40 is maintained in its normal horizontal initial position relative to its pivot axis 41, and the platform 32 of the cutting assembly 30 is maintained in its initial horizontal position relative to its pivot axle 27.

In order to swing the cutting tool 31 downwardly toward the work table, while the support 20 is held in this lowermost adjusted height position, the pedal 40 is de pressed or pivotally moved from its initial horizontal position about its pivot pin 41. The pedal 40 upon being depressed acts through the lift link 63 to rotate or swing the rocker arm 55 upwardly about the pivot pin 66. Such pivotal movement of the rocker arm 55 causes an upward movement of the heighth adjustment bar 50, and hence causes a pivotal movement of the cutting assembly 30 counterclockwise (FIG. 1) so as to lower the cutting tool 31 toward the work table 16.

It is seen that while the support 20 is maintained in its lowermost position, or in fact is maintained in any adjusted heighth position, the link stabilizer 61 fixed to the support 29 holds the floating link 63 in a stationary position, and hence holds the floating pivot pin 66 in a stationary position about which the rocker arm 55 can rotate.

When the pedal 40 is raised, as for example back to its initial horizontal position, the rocker arm 55 is rotated clockwise (FIG. 1) about the pivot pin 66 to cause a corresponding clockwise movement of the cutting assembly 30 about its pivotal axis provided by axle 27, and thereby raise the cutting tool 31 away from the work table 16.

If it is desired to raise the cutting assembly 30, the operator raises the handle arm 72 to rotate the manual element 70 clockwise, and hence actuate the linkage means 82, 81, 83 and 84 so as to raise the support 26 with the assistance of tensional force exerted by spring 86. After the support is located in the desired raised position the locking member 76 is again tightened to fix the pivoted adjusted position of manual element 70. The uppermost position of support 24 and the resultant position assumed by manual element 70 and the interconnecting linkage means is shown in FIG. 3.

It will be noted that the pedal 40 is maintained in its initial horizontal position relative to its pivotal axis upon raising the support 20. If it were not for the particular structure and connection of the stabilizer means provided by the link stabilizer 61 and the floating link 63, there would be a tendency for the cutting assembly 30 to rotate about its axle 27 in a clockwise direction (FIG. 1) which would further raise the cutting tool 31 in a direction away from the work table 16. It is desirable to hold the initial position of the cutting assembly 30 relative to its pivot axle 27 while the support and cutting assembly 30 are raised as a unit, and at the same time hold the pedal 40 in its initial position.

When the support 20 is raised, the link stabilizer 61 rotates the floating link 63 about its pivot pin 64 in a counterclockwise direction from the position shown in FIG. 1 to the position illustrated in FIG. 3. Because the rocker arm 55 is attached directly to the floating link 63 by the pivot pin 66, the pivot pin 66 acts to rotate the rocker arm 55 in a counterclockwise direction. It will be noted that the pivot pin 66 moves in an arc upwardly about the pivot pin 64.

As the rocker arm 55 is rotated as described above upon raising the support 20, the heighth adjustment bar 50 is raised and thereby maintains the cutting assembly 30 in the initial horizontal position relative to its axle 27.

Thus it is seen that in any adjusted heighth position of the cutting assembly 30 upon reciprocation of the support 20, the initial position of the cutting assembly 30 about its axle 27 and the initial position of pedal 40 relative to its pivot pin 41, is maintained. Furthermore, in any adjusted heighth position of the cutting assembly 30 and of support 20, the pedal 40 can be moved from its initial position about its pivotal axis to swing the cutting assembly 39 about its axle 27 in order to swing the cutting tool 31 toward and away from the work table 16.

Although the invention has been described by making detailed reference to a single preferred embodiment, such detail is to be understood in an instructive, rather than in any restrictive sense, many variants being possible within the scope of the claims hereunto appended.

I claim as my invention:

1. In a cutting machine, a frame, a support reciprocally mounted on said frame, a cutting assembly swingably mounted on said support, a manually-actuated element pivoted to said frame, a lever pivoted to said frame, a link attached to said lever so as to be pivoted therewith,

a bar extending between the support and link, said bar being pivoted to said link and to said support, a rod pivotally interconnecting the said manual element to said lever for pivoting the lever upon pivotal actuation of said element so as to reciprocate said support, and a spring operatively interconnecting the lever to said frame and tending to maintain said support substantially midway between its range of reciprocating movement.

2. In a cutting machine, a frame having a pair of side sleeves, a support including a pair of posts slidably mounted in said sleeves for reciprocation of said support, a cutting assembly swingably mounted on said support, a shaft extending transversely of the frame and pivotally mounted thereon, a link having one end attached to said shaft, a bar having one end pivoted to the other end of said link and having its other end pivoted to said support, a lever having one end attached to said shaft, a manually-actuated element pivoted to said frame, a rod having one end pivoted to said element and having its other end pivoted to the other end of said lever for pivoting the lever upon pivotal actuation of said element so as to reciprocate said support, and a spring opera tively interconnecting the lever to said frame and tending to maintain said support substantially midway between its range of reciprocating movement.

3. In a cutting machine, a frame, a support reciprocally mounted on said frame, a cutting assembly swingably mounted on said support, a shaft extending transversely of the frame and pivotally mounted thereon, a lever attached to said shaft at one side of said frame, a manually actuated element pivoted to the same side of said frame, a rod pivotally interconnecting said manual element and said lever for rotating said shaft upon pivotal actuation of said element, a link attached to..said shaft and rotatable therewith, said link being spaced inwardly from said lever toward the center of said frame, a bar pivotally interconnecting said link to said support, said link and bar reciprocating said support upon rotation of said shaft, and a spring operatively interconnecting the lever to said frame and tending to maintain said support substantially midway between its range of reciprocating movement,

4. In a cutting machine, a frame, a support reciprocally mounted on said frame, a cutting assembly swingably mounted on said support, a manually-actuated element pivoted to said frame, linkage means operatively interconnecting the said element to'the support for reciprocating the support upon pivotal actuation of said element, said linkage means including a shaft extending transversely of the frame and pivotally mounted thereon,. a lever having one end attached to said shaft at one side: of said frame, a rod having one end pivotally connected. to the other end of said lever and having its other end pivoted to said manual element, a link having one end'.

attached to said shaft, said link being spaced inwardly from said lever toward the center of said frame, a barhaving one end pivotally connected to the other end of said link and having its other end pivotally connected to said support, and a spring interconnecting said linkage means with said frame and tending to maintain said support substantially midway between its range of reciproeating movement.

5. In a cutting machine, a frame, a support reciprocally mounted on said frame, a manually-actuated ele-- ment pivoted to said frame, linkage means operatively interconnecting the said element to the support for re-- ciprocatihg the support upon pivotal actuation of saidv element, said linkage means comprising a lever pivoted.

1 to said frame, a rod pivotally interconnecting saidmanuall element andsaid lever, a link attached to said lever soas to be rotatable therewith, a bar pivotally interconnecting said link to said support, and a spring attached to said linkage means tending to maintain said support substantially' midway between its range of reciprocating movement.

6. In a cutting machine, a frame, a support recipro-- cally mounted on said frame, a cutting assembly swing ably mounted on said support, a manually-actuated ele-- ment pivoted to said frame, linkage means operatively interconnecting the said element to the support for reciprocating the support upon pivotal actuation of said element, a plate attached to said element, the plate being provided with an arcuate slot, a locking member carried by saidframe and extending through said slot, said lock-- ing member selectively fixing said element in adjusted.

" pivoted position, and a spring interconnecting said link-- age means with said frame and tending to maintain'said -'suppo rt substa'ntially midway between its range of reciprocating movement.

7. In a cutting machine, a frame, a support reciprocally mounted on said frame, a cutting assembly swingably mounted on said support, a manually-actuated ele-- ment pivoted to said frame, a linkage means operatively interconnecting the said element to the support for reciprocating the support upon pivotal actuation of said element, a plate attached to said element, the plate being provided with an arcuate slot, the locking member carried by said frame and extending through said slot, said locking member selectively fixing said element in adjusted pivoted position, said linkage means comprising a lever having one end pivoted to said frame, a rod having one end pivotally attached to the other end of said lever and having its other end pivotally attached to said manual element, a link having one end attached to said lever soas'to be rotatable therewith, a bar having one end pivotally attached to the other end of said link and having its other end pivotally attached to said support, and a spring attached to said linkage means and to said frame, said spring tending to maintain said support substantially midway between its range of reciprocating movement.

8. In a cutting machine, a frame, a support reciprocally mounted onsaid frame, a cutting assembly swingably mounted on said support, a manually-actuated element pivoted to said frame, a lever pivoted to said frame, a link attached to said lever so as to be pivoted therewith, a bar extending between the support and link, said bar'being pivoted to said link and to said support, a rod pivotally interconnecting the said manual element to said lever for pivoting the lever upon pivotal actuation of said element so as to reciprocate said support, a plate attached to said element, the plate being provided with an arcuate slot, a locking member carried by said frame and extending through said slot, said locking member seposition, and a spring operatively interconnecting the lever to said frame and tending to maintain said support substantially midway between its range of reciprocating movement.

9. In a'cutting machine, a frame having a pair of side sleeves, a support including a pair of posts' slidably mounted in said sleeves for reciprocation of said support, a cutting assembly swingably mounted on said support, a shaft extending transversely of the frame and pivotally mounted thereon, a link having one end attached to said shaft, a bar having one end pivoted to the-other end of said link and having its other end pivoted to said support, a lever having one end attached to said shaft, a manually-actuated element pivoted to said frame, a rod having one end pivoted to said manualelement and having its other end pivoted to the other end of said lever, a plate attached to said manual element, the plate being provided with an arcuate slot, a locking member carried by said-frame and extending through said slot, said locking member selectively fixing said manual element in adjusted pivoted position, and a spring operatively interconnecting the lever to said frame and tending to maintain said support substantially midway between its range of reciprocating movement.

10. In a cutting machine, a frame, a support reciprocally mounted on said frame, a cutting assembly swingably mounted on-said support, a manually-actuated element pivoted to said frame, linkage means operatively interconnecting the said manual element to the support for reciprocating the support upon pivotal actuation of said element, said linkage means comprising a shaft rotatively mounted on said frame and extending transversely of said frame, a lever attached to said shaft and located at one side of said frame, a rod pivotally interconnecting the lever to said manual element, a link attached to said shaft and spaced from said lever toward the center of said frame, a bar pivotally interconnecting said link to said support, a plate attached to-said manual element, the plate being provided with an arcuate slot, a locking member carried by said frame and extending through said slot, said locking member selectively fixing said element in adjusted pivoted position, and a spring operatively connected to said linkage means tending to maintain said support substantially midway between its range of reciprocating movement.

11. In a cutting machine, a frame, a support reciprocally mounted on said frame, a cutting assembly swingably mounted on said support, a manually-actuated element pivoted to the front of said frame at one side, linkage means operatively interconnecting the said manual element to the support for reciprocating the support upon pivotal actuation of said manual element, said linkage means comprising a shaft extending transversely of the frame and pivotally mounted thereon, a lever having one end attached to the shaft at the same side of the frame as said manual element, a rod having one end pivotally attached to the other end of said lever and having its other end pivotally attached to said manual element, a link having one end attached to said shaft so as to be rotatable therewith, said link being spaced from said lever toward the center of said frame, a bar having one end pivotally attached to the other end of said link and having its other end pivotally attached to said support, a plate attached to said manual element, the plate being provided with an arcuate slot, a locking handle carried by said frame and extending through said slot, said locking handle selectively fixing said manual element in adjusted pivoted position, and a spring having one end operatively connected to said linkage means and the other end attached to said frame, said spring tending to maintain the support substantially midway between the range of its reciprocating movement.

12. In a cutting machine, a frame, a support reciprocatively mounted on said frame, a manually-actuated element mounted on said frame, linkage means operatively interconnecting the said element to the support for reciprocating the support upon actuation of said element, said linkage means comprising a lever pivoted to said frame, a rod pivotally connected to said lever and operatively connected to said manually-actuated element, a link 10 5 range of reciprocating movement.

References Cited in the file of this patent UNITED STATES PATENTS 2,863,440 Harclerode Dec. 9, 1958 

